Translational research projects studying interstitial lung disease examine the pathogenesis of pulmonary fibrosis within subpopulations of patients, focussing on genetic effects. Diseases of interest include sporadic and genetic subtypes of pulmonary fibrosis. Thus far, at least two hundred patients have been enrolled in four clinical research protocols (i.e., 99-HL-0056, 99-HL-0068, 99-HL-0069, 04-H-0211). Analyses of patient-derived specimens (e.g., genomic DNA, serum, plasma, bronchoalveolar lavage cells and fluid, lung tissue) are being performed to study and compare genetic polymorphisms, gene and protein expression, and clinical findings (e.g., lung physiology, chest radiography, DTPA lung clearance scan). These pulmonary fibrosis protocols have generated collaborations with several intramural and extramural investigators. High-resolution computed tomography and aerosolized DTPA lung clearance scan findings are being examined by NIH Clinical Center researchers, Drs. Nilo Avila and Clara Chen, respectively. Dr. Ronald Goldstein, Boston University, and Dr. Ivan Rosas, University of Pittsburgh, will analyze biomarkers of fibrosis. Collaborations with Dr. Jonathan Orens, Johns Hopkins University, and Dr. Steven D.